Finally, the homogeneous nucleation is investigated and depicted
in Fig. REF . From the fast cooling liquid branch drawn
in Fig. REF  a configuration is taken at 600 K and the
simulation is restarted in the \(NPT\)  ensemble at ambient pressure.
At such a high degree of undercooling \(\Delta T = (T_M-T)/T_M =0.38\) 
an extremely fast nucleation process is observed
[1]}, [2]}. Given the smallness of the simulation
box containing here 10976 atoms, a genuine statistics to obtain
the nucleation rate is out of reach [3]}, [4]}.
However, from IS configurations collected before the onset of
nucleation occurring at about 50 ps, a CNA analysis [5]}
was performed. Inspection of embryos with atoms having a crystalline
ordering (either fcc, hcp or bcc) showed that they dissolve back
to the liquid with a size less than 90 atoms. The latter value
does not represent per se the size critical nucleus but
rather a lower limit. As expected, the main crystalline phase during
the growth was identified as fcc, as can be seen in Fig. REF ,
but a significant hcp ordering also appears during the nucleation
and remains as stacking fault after complete solidification of the
simulation box.
